Iphone USB tethering

This page is inspired by Android USB tethering. It only documents the differences.

Tested devices

• iPhone 4S, iOS5
• iPhone 5, iOS6
• iPhone 5S, iOS9
• iPhone 7, iOS 14.7.1

Kernel

KERNEL Linux 4.4

Device Drivers 
  -> Network device support (NETDEVICES)
    -> USB Network Adapters (USB_NET_DRIVERS)
         <*>  Apple iPhone USB Ethernet driver (USB_IPHETH)

Tools needed

You will also need app-pda/usbmuxd and app-pda/ifuse from the default portage tree.

root #emerge --ask app-pda/usbmuxd app-pda/ifuse

ipheth interface

If everything is installed successfully, plug in the iPhone with USB cable. You should see something like:

CODE dmesg: iPhone ipheth

[    2.080017] usb 8-1: new high-speed USB device number 2 using ehci_hcd
[    2.215940] usb 8-1: New USB device found, idVendor=05ac, idProduct=12a0
[    2.215946] usb 8-1: New USB device strings: Mfr=1, Product=2, SerialNumber=3
[    2.215950] usb 8-1: Product: iPhone
[    2.215953] usb 8-1: Manufacturer: Apple Inc.
[    2.215956] usb 8-1: SerialNumber: xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
[   26.988569] ipheth 8-1:4.2: Apple iPhone USB Ethernet device attached
[   26.988939] usbcore: registered new interface driver ipheth

A new network interface eth1 plugged by ipheth can be found, after running DHCP on it:

root #ip a show eth1

4: eth1: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UNKNOWN qlen 1000
    link/ether 9e:20:7b:6b:94:bd brd ff:ff:ff:ff:ff:ff
    inet 172.20.10.2/28 brd 172.20.10.15 scope global eth1
    inet6 fe80::9c20:7bff:fe6b:94bd/64 scope link 
       valid_lft forever preferred_lft forever

If no output is observed from dmesg, try mounting the iphone via ifuse:

root #ifuse /mnt/

The device must be unlocked and incoming connections must be allowed while ifuse is mounting. Ifuse will guide provide guidance though the process; follow its instructions and try mounting until it succeeds.

udev trigger

The hotplug feature of OpenRC can be used to set up the ipheth interface automatically.

sys-fs/udev-init-scripts ships /lib/udev/net.sh, which can be used to hotplug network interfaces. The main part of the script is

FILE /lib/udev/net.shnet interface hotplug

IFACE=$1
ACTION=$2
...
SCRIPT=/etc/init.d/net.$IFACE
...
IN_HOTPLUG=1 "${SCRIPT}" --quiet "${ACTION}"

and it can be called with a udev rule:

FILE /lib/udev/rules.d/90-iphone-tether.rulesnet.sh trigger

# udev rules for setting correct configuration and pairing on tethered iPhones
ATTR{idVendor}!="05ac", GOTO="ipheth_rules_end"

# Execute pairing program when appropriate
ACTION=="add", SUBSYSTEM=="net", ENV{ID_USB_DRIVER}=="ipheth", SYMLINK+="iphone", RUN+="ipheth-pair", RUN+="net.sh eth1 start"
SUBSYSTEM=="net", ACTION=="remove", ENV{ID_USB_DRIVER}=="ipheth", SYMLINK+="iphone", RUN+="net.sh %k stop"

LABEL="ipheth_rules_end"

Enable hotplug to eth1, the ipheth device:

FILE /etc/rc.confrc_hotplug

# rc_hotplug is a list of services that we allow to be hotplugged.
# By default we do not allow hotplugging.
# A hotplugged service is one started by a dynamic dev manager when a matching
# hardware device is found.
# This service is intrinsically included in the boot runlevel.
# To disable services, prefix with a !
# Example - rc_hotplug="net.wlan !net.*"
# This allows net.wlan and any service not matching net.* to be plugged.
# Example - rc_hotplug="*"
# This allows all services to be hotplugged
rc_hotplug="net.eth1"

add net.eth1:

root #ln -s /etc/init.d/net.{lo,eth1}

After plugging in the iPhone, we can see the service started:

root #rc-status

...
Dynamic Runlevel: hotplugged
 net.eth1                        [  started  ]
...